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1.
J Environ Sci (China) ; 124: 11-18, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36182121

RESUMO

Many per- and polyfluoralkyl substances (PFASs) may disrupt maternal thyroid hormone homeostasis in pregnancy. Concerns should be raised regarding the PFASs exposure in pregnant women because thyroid hormones are involved in the early development of the fetus. In this study, we measured the concentrations of 13 PFASs, including five novel short-chain PFASs, in serum from 123 pregnant women in Beijing, China. Linear regression models were used to investigate the association between thyroid-stimulating hormone (TSH) or free thyroxine (FT4) levels and PFASs concentrations under consideration of the impacts of pregnancy-induced physiological factors. We found that perfluorobutanoic acid (PFBA) (ß=0.189, 95%CI=-0.039, 0.417, p=0.10) and perfluorodecanoic acid (PFDA) (ß=-0.554, 95%CI=-1.16, 0.049, p=0.071) were suggestive of significant association with TSH in thyroid peroxidase antibody (TPOAb) negative women. No association was observed between all PFASs and FT4 levels after controlling for these confounding factors, such as BMI, gestational weight gain and maternal age. These findings suggest that it should pay more attention to the association between thyroid hormone levels and short-chain PFASs concentrations. Future studies could consider a greater sample and the inclusion of other clinical indicators of thyroid function, such as free T3 and total T3.


Assuntos
Fluorcarbonetos , Feminino , Humanos , Iodeto Peroxidase , Gravidez , Gestantes , Hormônios Tireóideos , Tireotropina , Tiroxina
2.
Sci Total Environ ; 856(Pt 1): 159074, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36181807

RESUMO

Ultraviolet filters are commonly used in various cosmetic products. Due to their huge consumption ultraviolet filters become a part of the environment. Octinoxate is a commonly used ultraviolet filter that is widely detected in the aquatic environment. In our study, we investigated whether this ultraviolet filter is able to disrupt thyroid hormone regulation after six weeks of exposure in rainbow trout (Oncorhynchus mykiss). Thyroid hormones play crucial role in development and regulation of the organism and its disruption could cause the whole-body imbalance. Our study includes a compilation of in vivo and in vitro tests. The results of the in vivo experiment revealed a significant increase in thyroxine hormone in plasma for the highest tested dose of octinoxate (i.e. 395.6 µg/kg). We examined selected tissues (liver and cranial kidney) to determine the mRNA expression of genes involved in thyroid hormones regulation. The analysis confirmed downregulation of deiodinase 2 mRNA expression for the highest tested dose (i.e. 395.6 µg/kg) and downregulation of paired box 8 mRNA for medium (96 µg/kg) and the highest octinoxate dose (395.6 µg/kg.) only in cranial kidney. In vitro analysis indicated that octinoxate does not elicit (anti-)thyroid activity via thrß and does not behave as a transthyretin ligand. Based on our results, octinoxate has a potential to act as a thyroid hormone disruptor, but further research required to better understand the entire regulatory mechanism.


Assuntos
Oncorhynchus mykiss , Hormônios Tireóideos , Animais , Tiroxina , Oncorhynchus mykiss/metabolismo , RNA Mensageiro/metabolismo
3.
Artigo em Inglês | MEDLINE | ID: mdl-36210033

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are well-known contaminants with widespread distribution in environment and food. Phenanthrene is one of the most abundant PAHs in food and aquatic environment and generates reproductive and developmental toxicity in zebrafish. Nonetheless, whether phenanthrene caused sex-specific thyroid disruption in adult zebrafish is unclear. To determine this, adult zebrafish (male and female) were treated with phenanthrene (0, 0.85, 8.5, and 85 µg/L) for 60 days. After the treatment period, we assessed the concentrations of thyroid hormones (THs) and expression levels of genes in the hypothalamic-pituitary-thyroid (HPT) axis. The results showed that phenanthrene exposure can lead to thyroid disruption in both male and female zebrafish. Exposure to phenanthrene dramatically reduced the levels of L-thyroxine (T4) and L-triiodothyronine (T3) in both male and female zebrafish, with a similar trend in both. However, the genes expression profiles of hypothalamic-pituitary-thyroid (HPT) axis were sex-specific. In all, the present study demonstrated that phenanthrene exposure could result in sex-specific thyroid disruption in adult zebrafish.


Assuntos
Fenantrenos , Poluentes Químicos da Água , Animais , Feminino , Masculino , Peixe-Zebra/metabolismo , Glândula Tireoide/metabolismo , Tri-Iodotironina/metabolismo , Tiroxina/metabolismo , Hormônios Tireóideos/metabolismo , Fenantrenos/toxicidade , Fenantrenos/metabolismo , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/metabolismo
4.
Horm Metab Res ; 54(2): 67-75, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35130567

RESUMO

Resistance to thyroid hormone syndrome (RTHS) is defined as increased thyroxine and triiodothyronine associated with normal or increased thyrotropin. This is usually due to a pathogenic variant of the gene coding for thyroid hormone receptor B (THRB). THRB is a rare genetic disorder characterized by an altered response of target tissue to the thyroid hormone action. Retrospective cross-sectional observational study with diagnosis of RTHS evaluated in secondary and tertiary hospitals for 6 years, from 2014 to 2020, in order to describe variables including age, sex, anthropometric data, clinical and biochemical characteristics of patients, who were divided according to age, in a pediatric group from 0 to 14 years (index cases), and an adult group composed of adult relatives of index cases. A molecular analysis of the THRB gene was performed. The total retrospective cohort included 7 pediatric patients and 15 adults. We found 22 cases with a clear male predominance (14/22). Mean age is 24.8 years old (22 days-70 years). Patients were referred because of symptoms 18.2% (4/22), analysis results 22.7% (5/22), or familial study 59.1% (13/22). About 31.8% (7/22) cases show goiter, 31.8% (7/22) sympathetic symptoms and 13.6% (3/22) abnormalities in behavior. In most cases, 77.3%, (17/22) show familial background of thyroid abnormalities. It is important to remark that 18.2% (4/22) relatives received previous incorrect treatments such as thyroidectomy, because of wrong diagnosis. In conclusion, a better understanding of RTHS, its prompt molecular diagnosis and genetic counseling, could avoid unnecessary tests and inappropriate treatments.


Assuntos
Síndrome da Resistência aos Hormônios Tireóideos , Adolescente , Adulto , Criança , Pré-Escolar , Estudos Transversais , Humanos , Lactente , Recém-Nascido , Masculino , Mutação , Estudos Retrospectivos , Receptores beta dos Hormônios Tireóideos/genética , Síndrome da Resistência aos Hormônios Tireóideos/diagnóstico , Síndrome da Resistência aos Hormônios Tireóideos/genética , Tireotropina , Tiroxina , Tri-Iodotironina , Adulto Jovem
5.
Radiology ; 305(3): 746-750, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36409615

RESUMO

HISTORY: An 11-year-old girl presented to the pediatric gastroenterology outpatient department of our institution with gradually increasing painless abdominal distention. The distention started 2 years earlier and was not associated with any other constitutional symptoms, vomiting, diarrhea, jaundice, hematemesis, or melaena. She reported early satiety and heaviness in the lower abdomen. The abdominal swelling was predominantly in the infraumbilical region and was soft at palpation. She was the first child of nonconsanguineous parents and had an uneventful perinatal course after a normal vaginal delivery. Her developmental milestones were normal. She had an average scholastic performance at school. There was no history of visual problems, seizures, or inappropriate behaviors. She had an early menarche 2 years previously. Her menstrual cycles were regular, and there was no abnormal vaginal discharge. Her breast development was normal (Tanner stage III), while pubic and axillary hair were absent (Tanner stage I). She was short for her age (104 cm; normal range, 120-154 cm). There was no history of short stature among her siblings or parents. Laboratory investigations were performed to measure thyroid-stimulating hormone (1354.34 µIU/mL; normal range, 0.35-5.5 µIU/mL), triiodothyronine (<2.5 ng/dL [0.0385 pmol/L]; normal range, 100-200 ng/dL [1.54-3.08 pmol/L]), thyroxine (1.35 µg/dL [17.37 nmol/L]; normal range, 5-12 µg/dL [64.35-154.44 nmol/L]), ß-human chorionic gonadotropin (<1.2 mIU/mL; normal, <5 mIU/mL), luteinizing hormone (0.08 mIU/mL; normal range, 0.1-6.0 mIU/mL), and follicle-stimulating hormone (6.93 mIU/mL; normal range, 0.3-2.0 mIU/mL) levels. Complete blood count was normal. An abdominal mass was suspected, and abdominopelvic CT was performed and followed by US; these examinations revealed multiple large cysts in both ovaries. The uterus was pubertal in shape, and endometrial thickness was 9 mm, representing normal follicular phase measurement. Serum CA-125 and inhibin levels were normal. To evaluate short stature, radiographs of the hand and pelvis were obtained as part of a limited skeletal survey, keeping in mind the possible skeletal changes associated with hypothyroidism. In view of the hypothyroidism, US of the neck was also performed. Treatment was started based on the clinical and radiologic parameters, and the child's condition improved with medical treatment.


Assuntos
Hipotireoidismo , Puberdade Precoce , Humanos , Criança , Feminino , Puberdade Precoce/complicações , Puberdade Precoce/diagnóstico , Puberdade Precoce/tratamento farmacológico , Tiroxina/uso terapêutico , Hipotireoidismo/complicações , Síndrome , Ovário
6.
Front Endocrinol (Lausanne) ; 13: 1044691, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36387853

RESUMO

The clinical availability of tissue-specific biomarkers of thyroid hormone (TH) action constitutes a "holy grail" for the field. Scientists have investigated several TH-dependent markers, including the tissue content of triiodothyronine (T3)-the active form of TH. The study of animal models and humans indicates that the T3 content varies among different tissues, mostly due to the presence of low-affinity, high-capacity cytoplasmic T3 binding proteins. Nonetheless, given that T3 levels in the plasma and tissues are in equilibrium, T3 signaling is defined by the intracellular free T3 levels. The available techniques to assess tissue T3 are invasive and not clinically applicable. However, the tracer kinetic studies revealed that serum T3 levels can accurately predict tissue T3 content and T3 signaling in most tissues, except for the brain and pituitary gland. This is true not only for normal individuals but also for patients with hypo or hyperthyroidism-but not for patients with non-thyroidal illness syndrome. Given this direct relationship between serum and tissue T3 contents and T3 signaling in most tissues, clinicians managing patients with hypothyroidism could refocus attention on monitoring serum T3 levels. Future clinical trials should aim at correlating clinical outcomes with serum T3 levels.


Assuntos
Hipotireoidismo , Tiroxina , Animais , Humanos , Cinética , Hormônios Tireóideos , Tri-Iodotironina , Testes de Função Tireóidea
7.
Arch Iran Med ; 25(7): 417-421, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-36404507

RESUMO

BACKGROUND: Hypothyroidism is the most common hormonal deficiency worldwide; however, there is limited data about its prevalence in the children and adolescents of the Middle East. METHODS: The prevalence of hypothyroidism were calculated by dividing the number of patients purchasing levothyroxine in 1397 Solar-Hijri year (Correlate with March 2018-February 2019) by the population at risk (per 10000 persons). Data were collected from the Iran health insurance organization registration records and family physician databases of health vice-chancellor of Shiraz University of Medical Sciences. RESULTS: The present study shows that the prevalence of levothyroxine treated population aged under 18 years is 13 in 10000 in the Fars province and it is more common in females (17 in 10000 in females versus 9 in 10000 in males). This study also revealed that the prevalence of hypothyroidism was different in various age groups and increased in older children and adolescents after pubertal ages. Also, an increase in the female: male ratio of prevalence was more obvious during and after puberty. CONCLUSION: Our study showed that the prevalence of congenital hypothyroidism was 3/10000 in southern Iran. Also, the prevalence of hypothyroidism in children and adolescents was totally 13/10000 population, and this prevalence increased in older age and female gender. This prevalence was close to the data from iodine sufficient areas in Europe and the United States.


Assuntos
Hipotireoidismo Congênito , Tiroxina , Humanos , Adolescente , Criança , Masculino , Feminino , Idoso , Tiroxina/uso terapêutico , Prevalência , Irã (Geográfico)/epidemiologia , Prescrições
8.
JAMA Netw Open ; 5(11): e2240823, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36346629

RESUMO

Importance: Clinical hyperthyroidism accelerates bone resorption without compensatory bone formation, reducing bone density and increasing the risk of fracture. The association between subclinical hyperthyroidism and fracture risk is less clear. Objective: To investigate the association of endogenous subclinical thyroid dysfunction and fracture risk, independent of clinical confounders. Design, Setting, and Participants: This cohort study included 10 946 participants from the Atherosclerosis Risk in Communities Study, an ongoing prospective cohort study of community-dwelling individuals conducted from 1987-1989 through December 31, 2019, in Washington County, Maryland; Forsyth County, North Carolina; Jackson, Mississippi; and the suburbs of Minneapolis, Minnesota. Participants were not taking thyroid medications and had no history of fractures. Exposures: Thyrotropin and free thyroxine levels were measured at visit 2 (1990-1992). Subclinical hyperthyroidism was defined as a thyrotropin level lower than 0.56 mIU/L, subclinical hypothyroidism as a thyrotropin level higher than 5.1 mIU/L, and euthyroidism as a thyrotropin level of 0.56 to 5.1 mIU/L, with normal free thyroxine levels from 0.85 to 1.4 ng/dL. Main Outcomes and Measures: Incident fracture was ascertained using hospitalization discharge codes through 2019 and linkage to inpatient and outpatient Medicare claims through 2018. Results: Of 10 946 participants (54.3% women; mean [SD] age, 57 [5.7] years), 93.0% had euthyroidism, 2.6% had subclinical hyperthyroidism, and 4.4% had subclinical hypothyroidism. During a median follow-up of 21 years (IQR, 13.0-27.3 years), there were 3556 incident fractures (167.1 per 10 000 person-years). The adjusted hazard ratios of fracture were 1.34 (95% CI, 1.09-1.65) for those with subclinical hyperthyroidism and 0.90 (95% CI, 0.77-1.05) for those with subclinical hypothyroidism compared with individuals with euthyroidism. Among those with normal free thyroxine levels, thyrotropin levels in the lower-than-normal range were significantly associated with higher fracture-related hospitalization risk; fracture risk was greater among individuals with thyrotropin concentrations below 0.56 mIU/L. Conclusions and Relevance: This community-based cohort study suggests that subclinical hyperthyroidism was an independent risk factor associated with fracture. The increased risk for fracture among individuals with a thyrotropin level lower than 0.56 mIU/L highlights a potential role for more aggressive screening and monitoring of patients with subclinical hyperthyroidism to prevent bone mineral disease.


Assuntos
Fraturas Ósseas , Hipertireoidismo , Hipotireoidismo , Doenças da Glândula Tireoide , Humanos , Feminino , Idoso , Estados Unidos , Pessoa de Meia-Idade , Masculino , Tiroxina , Estudos de Coortes , Estudos Prospectivos , Medicare , Hipertireoidismo/complicações , Hipertireoidismo/epidemiologia , Hipotireoidismo/complicações , Hipotireoidismo/epidemiologia , Tireotropina , Fraturas Ósseas/epidemiologia , Fraturas Ósseas/etiologia
9.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi ; 40(10): 733-736, 2022 Oct 20.
Artigo em Chinês | MEDLINE | ID: mdl-36348552

RESUMO

Objective: To investigate the effect of low-dose X-ray ionizing radiation on thyroid function of radiation workers. Methods: From January to December 2021, a total of 1039 medical workers in some tertiary hospitals in Wuhan were selected as the survey subjects, of which 518 radiation workers were selected as the exposure group, and 521 non-radiation workers were selected as the control group. The general conditions of the two groups were collected, and 5 indicators of thyroid function were measured, including total thyroxine (TT(4)) , total triiodothyronine (TT(3)) , free triiodothyronine (FT(3)) , thyroid stimulating hormone (TSH) , and free thyroxine (FT(4)) . The annual cumulative dose of ionizing radiation exposure in the exposure group was collected. Pearson χ(2) test and independent sample t test were used to compare the general conditions, 5 indicators of thyroid function and abnormal rate between the two groups. Linear regression model was used to analyze the correlation between the annual cumulative dose and 5 indicators of thyroid function in the exposure group. Binary logistic regression was used to analyze the influencing factors of thyroid dysfunction in the exposure group. Results: The TT(4) levels of the workers in the control group and the exposure group were (7.95±1.07) µg/dl and (8.26±1.41) µg/dl, respectively, and the FT(4) levels were (16.33±2.19) pmol/L and (17.15±2.42) pmol/L, respectively, the rate of thyroid dysfunction was 4.80% (25/521) and 8.49% (44/518) , and the above differences were statistically significant (P<0.05) . Linear regression analysis showed that the annual cumulative dose of the exposure group was significantly correlated with TT(4), TT(3), FT(4), and TSH (P<0.05) . For every 1 mSv increase in the annual cumulative dose, TT(4) increased by 1.661 µg/dl, FT(4) increased by 1.422 pmol/L, TT(3) decreased by 0.113 ng/ml, and TSH decreased by 0.731 µIU/ml. Binary logistic regression analysis showed that the older the radiation workers, the higher the risk of thyroid dysfunction (OR=1.080, 95% CI: 1.016-1.148, P=0.013) ; the greater the annual cumulative dose, the higher the risk of thyroid dysfunction (OR=6.400, 95%CI: 1.796-22.811, P=0.004) . Conclusion: The annual cumulative dose of low-dose X-ray ionizing radiation is positively correlated with thyroid function TT(4) and FT(4) of radiation workers, and negatively correlated with TT(3) and TSH; the greater the age and annual cumulative dose, the higher the risk of thyroid dysfunction.


Assuntos
Tiroxina , Tri-Iodotironina , Humanos , Glândula Tireoide/efeitos da radiação , Raios X , Tireotropina , Radiação Ionizante
10.
Georgian Med News ; (328-329): 141-147, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36318859

RESUMO

The systematization of literature data on the use of ß-adrenoblockers in patients with heart failure and concomitant thyroid pathology was carried out, and the results of our own study were presented. It has been suggested that the final chapter in the history of the use of ß-adrenoblockers in patients with heart failure with reduced left ventricular ejection fraction and thyroid pathology has not yet been written. Further studies are needed, including pharmacogenetic ones. The use of a selective ß-adrenoblockers - bisoprolol in patients with chronic heart failure with reduced left ventricular ejection fraction and concomitant low triiodothyronine syndrome does not lead to a decrease in the frequency of rehospitalization due to decompensation. At the same time, the frequency of rehospitalization in the group of patients with heart failure without low triiodothyronine syndrome is higher at a dose of 1.25-5.0 mg of bisoprolol compared with a higher dose. The effect of bisoprolol is reversed in patients with low triiodothyronine syndrome: the risk of re-hospitalization increases when the dose of bisoprolol is exceeded, there is a decrease in the serum level of triiodothyronine, an increase in thyroxine levels, a decrease in the ratio of triiodothyronine / thyroxine; further increase in the cavities of the heart and decrease in size. Probably, in patients with heart failure, against the background of low triiodothyronine syndrome, it is not advisable to titrate the dose of bisoprolol above 5 mg, and the time to titrate the drug to the indicated dose should be more than 63 days. Today it can be argued that, in general, recommendations for the use ß-adrenoblockers in patients with chronic heart failure with reduced left ventricular ejection fraction apply to patients with concomitant thyroid dysfunction, subject to the above restrictions.


Assuntos
Síndromes do Eutireóideo Doente , Insuficiência Cardíaca , Humanos , Bisoprolol/farmacologia , Volume Sistólico , Função Ventricular Esquerda , Antagonistas Adrenérgicos beta/farmacologia , Tri-Iodotironina , Tiroxina
11.
Front Endocrinol (Lausanne) ; 13: 1026262, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36329885

RESUMO

Clinical hypothyroidism is defined by the inadequate production of thyroid hormone from the thyroid gland to maintain normal organ system functions. For nearly all patients with clinical hypothyroidism, lifelong treatment with thyroid hormone replacement is required. The primary goal of treatment is to provide the appropriate daily dose of thyroid hormone to restore normal thyroid function for each individual patient. In current clinical practice, normalization of thyrotropin (TSH) level is the primary measure of effectiveness of treatment, however the use of a single biomarker to define adequate thyroid hormone replacement is being reevaluated. The assessment of clinical health outcomes and patient-reported outcomes (PROs), often within the context of intensity of treatment as defined by thyroid function tests (i.e., undertreatment, appropriate treatment, or overtreatment), may play a role in evaluating the effectiveness of treatment. The purpose of this narrative review is to summarize the prominent health outcomes literature in patients with treated hypothyroidism. To date, overall mortality, cardiovascular morbidity and mortality, bone health and cognitive function have been evaluated as endpoints in clinical outcomes studies in patients with treated hypothyroidism. More recent investigations have sought to establish the relationships between these end results and thyroid function during the treatment course. In addition to clinical event outcomes, patient-reported quality of life (QoL) has also been considered in the assessment of adequacy of hypothyroidism treatment. From a health care quality perspective, treatment of hypothyroidism should be evaluated not just on its effectiveness for the individual patients but also to the extent to which patients of different sociodemographic groups are treated equally. Ultimately, more research is needed to explore differences in health outcomes between different sociodemographic groups with hypothyroidism. Future prospective studies of treated hypothyroidism that integrate biochemical testing, PROs, and end result clinical outcomes could provide a more complete picture into the effectiveness of treatment of hypothyroidism.


Assuntos
Hipotireoidismo , Tiroxina , Humanos , Tiroxina/uso terapêutico , Qualidade de Vida , Estudos Prospectivos , Hipotireoidismo/tratamento farmacológico , Hormônios Tireóideos/uso terapêutico , Resultado do Tratamento
12.
BMC Med ; 20(1): 390, 2022 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-36344981

RESUMO

BACKGROUND: The influence of maternal levothyroxine treatment during pregnancy remains unclear. This study aimed to evaluate the associations of maternal levothyroxine treatment during pregnancy with the birth and neurodevelopmental outcomes in offspring. METHODS: This population-based cohort study was conducted among pregnant women using the Hong Kong Clinical Data Analysis and Reporting System. Mother-child pairs in Hong Kong from 2001 to 2015 were included and children were followed up till 2020. We defined the exposure group as mothers who were exposed to levothyroxine during pregnancy. Preterm birth and small for gestational age (SGA) were included as birth outcomes. Attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) were included as neurodevelopmental outcomes. Odds ratios (OR) or hazard ratios (HRs) with a 95% confidence interval (CI) were evaluated to assess the association of gestational levothyroxine use with offspring birth and neurodevelopmental outcomes respectively, using propensity score fine-stratification weighting and a Cox proportional hazards regression model. RESULTS: Among 422,156 mother-child pairs, 2125 children were born from mothers exposed to levothyroxine during pregnancy. A significantly increased risk of preterm birth was observed in children with maternal levothyroxine exposure during pregnancy, when compared to mothers who had no history of thyroid-related diagnoses or prescriptions (weighted OR [wOR]: 1.22, 95% CI: 1.07, 1.39). Similarly, an increased risk of preterm birth was found among children of gestational levothyroxine users, when compared to children of mothers who had used levothyroxine before but stopped during pregnancy (wOR: 2.16, 95% CI: 1.09, 4.25). Sensitivity analysis, by excluding mothers exposed to psychotropic or antiepileptic medications before or during pregnancy, also indicated a similar increased risk of preterm birth regarding the gestational use of levothyroxine (wOR: 1.26, 95% CI: 1.10, 1.45). No significant association was observed for the risk of SGA, ADHD, and ASD. CONCLUSIONS: There is no evidence that gestational use of levothyroxine is associated with SGA, ADHD, or ASD in offspring. Gestational levothyroxine treatment is associated with a higher risk of preterm birth. Such risk might be confounded by the underlying maternal thyroid disease itself, however, we cannot completely exclude the possible effect of gestational L-T4 treatment on offspring preterm birth. Our findings provided support to the current guidelines on the cautious use of levothyroxine treatment during pregnancy.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Transtorno do Espectro Autista , Nascimento Prematuro , Efeitos Tardios da Exposição Pré-Natal , Recém-Nascido , Gravidez , Feminino , Humanos , Estudos de Coortes , Tiroxina/efeitos adversos , Nascimento Prematuro/epidemiologia , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/epidemiologia
13.
Int J Mol Sci ; 23(21)2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36362134

RESUMO

Different serum thyroxine levels may influence the morphology of the inner ear during development. A well-developed organ of Corti (OC) is considered to be critical to the function of hearing. In our study, we treated mice with triiodothyronine (T3) and found that the opening of the OC occurred sooner than in control mice. We also observed an increased formation of acetylated microtubules and a decrease in the adhesion junction molecule P-cadherin the during opening of the OC. Our investigation indicates that thyroxin affects P-cadherin expression and microtubule acetylation to influence the opening of the OC.


Assuntos
Orelha Interna , Tiroxina , Camundongos , Animais , Tiroxina/farmacologia , Tiroxina/metabolismo , Microtúbulos/metabolismo , Órgão Espiral/metabolismo , Caderinas/genética , Caderinas/metabolismo
14.
Trends Endocrinol Metab ; 33(12): 804-816, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36344381

RESUMO

Thyroid hormones are essential metabolic and developmental regulators that exert a huge variety of effects in different organs. Triiodothyronine (T3) and thyroxine (T4) are synthesized in the thyroid gland and constitute unique iodine-containing hormones that are constantly regulated by a homeostatic feedback mechanism. T3/T4 activity in cells is mainly determined by specific transporters, cytosolic binding proteins, deiodinases (DIOs), and nuclear receptors. Modulation of intracellular T3/T4 level contributes to the maintenance of this regulatory feedback. µ-Crystallin (CRYM) is an important intracellular high-affinity T3-binding protein that buffers the amount of T3 freely available in the cytosol, thereby controlling its action. In this review, we focus on the molecular and pathological properties of CRYM in thyroid hormone signaling, with emphasis on its critical role in malignancies.


Assuntos
Proteínas de Transporte , Cristalinas , Humanos , Proteínas de Transporte/metabolismo , Cristalinas mu , Tri-Iodotironina/metabolismo , Tiroxina/metabolismo , Hormônios Tireóideos , Cristalinas/metabolismo
15.
Clin Lab ; 68(11)2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36378001

RESUMO

BACKGROUND: The aim was to investigate the relationship between the vitamin D (VitD) level and the incidence rate of subclinical hypothyroidism in patients with gestational diabetes mellitus (GDM) in early pregnancy. METHODS: Ninety eligible patients who underwent physical examination from March 2015 to September 2017 were selected. The levels of serum 25-hydroxyvitamin D (25-OH-VD), free thyroxine (FT4), free triiodothyronine (FT3), thyroid stimulating hormone (TSH), and thyroid peroxidase antibody (TPOAb) were measured. The correlations of VitD level with those of thyroid function-related indices were analyzed. RESULTS: The serum 25-OH-VD level was (17.82 ± 3.45) ng/mL in the 90 GDM patients in early pregnancy, including 64.44% patients in VitD deficiency group, 22.22% patients in VitD insufficiency group, and 13.33% in VitD sufficiency group. No significant differences in the levels of serum FT4, FT3, and TSH were found among different VitD groups (p > 0.05), but the level of TPOAb gradually decreased (p < 0.05). There was no significant difference in the incidence rate of subclinical hypothyroidism among different VitD groups (p > 0.05). VitD level was not correlated with those of FT4, FT3, and TSH (p > 0.05), but negatively correlated with that of TPOAb (p < 0.05). An increase of TPOAb level raised the risk of VitD deficiency in pregnant women (p < 0.05). Patients suffered from significant 25-OH-VD deficiency in spring and winter (p < 0.05). CONCLUSIONS: GDM patients in early pregnancy display VitD deficiency, and their serum 25-OH-VD level is affected by seasons and not significantly related to subclinical hypothyroidism. However, the increased level of TPOAb may raise the risk of VitD deficiency in pregnant women.


Assuntos
Diabetes Gestacional , Hipotireoidismo , Humanos , Feminino , Gravidez , Diabetes Gestacional/diagnóstico , Diabetes Gestacional/epidemiologia , Tireotropina , Testes de Função Tireóidea , Vitamina D , Tiroxina
16.
Chin Med J (Engl) ; 135(16): 1962-1968, 2022 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-36378137

RESUMO

BACKGROUND: Changes in thyroid hormone levels are commonly recognized characters among the elderly, which were reported to potentially influence incident frailty. Therefore, we examined the cross-sectional associations of thyroid hormones (THs) with frailty as well as the five components characterizing frailty (fatigue, resistance, ambulation, number of illnesses, and loss of weight) among the oldest-old. METHODS: Four hundred and eighty-seven community-dwelling oldest-old from a local community in Haidian District, Beijing, participated in our recruitment campaign between April 2019 and May 2020. The primary outcomes were a definitive diagnosis of frailty according to the FRAIL scale (Fatigue, Resistance, Ambulation, Illnesses, Loss of weight) and a positive score for each frailty subdomain. Demographic information (age, sex, marital status, and educational status), comorbidities, and details on the participants' lifestyles were recorded. Serum THs including free triiodothyronin (fT3), triiodothyronine (T3), free thyroxine (fT4), and thyroxine (T4) and thyroid stimulating hormone (TSH) levels were also measured at the beginning of our study. Logistic regressions were conducted to screen for potential risk factors for frailty and its subdomains. RESULTS: Among the total 487 subjects at enrollment, 60 (12.23%) of them were diagnosed with subclinical hypothyroidism and 110 (22.59%) of the total population scored positive for frailty. Logistic regression analyses adjusted for all potential confounders, showed that frailty was significantly associated with the serum TSH concentration (odds ratio [OR]: 1.06), fT3 concentration (OR: 0.54), and subclinical hypothyroidism score (OR: 2.18). The association between fT4 and frailty was absent in our observational study. The fT3/fT4 ratio characterizing peripheral hormone conversion was also tested to be correlated with frailty. CONCLUSION: Subclinical hypothyroidism, higher TSH level, lower fT3 level, and decreased fT3/fT4 ratio were all associated with frailty assessed by the FRAIL scale among the community-dwelling oldest-old, suggesting a relevant role of thyroid function in aging. Future longitudinal studies are warranted to determine the casual relationship between thyroid dysfunction and frailty in the oldest-old.


Assuntos
Fragilidade , Hipotireoidismo , Humanos , Idoso de 80 Anos ou mais , Idoso , Tiroxina , Estudos Transversais , Tireotropina , Vida Independente , Tri-Iodotironina , Testes de Função Tireóidea , Hormônios Tireóideos , Fadiga
17.
Med Sci Monit ; 28: e937957, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36352753

RESUMO

BACKGROUND Thyroid-stimulating hormone (TSH), which is regulated by the negative feedback of triiodothyronine (T3) and thyroxine (T4), is affected by cortisol (a stress hormone) and cytokines during allostasis. Thus, we assessed changes in TSH levels under stress and its potential as a stress marker in patients lacking T3 or T4 feedback after thyroid surgery. MATERIAL AND METHODS Three stress questionnaires (Korean version of the Daily Stress Inventory, Social Readjustment Rating Scale, and Stress Overload Scale-Short [SOSS]), an open-ended questionnaire (OQ), and thyroid function tests were administered twice to 106 patients enrolled from January 2019 to October 2020. RESULTS In a multiple generalized linear mixed-effect model (GLMM) involving 106 patients, the T3 and free T4 levels, OQ, body weight, extent of thyroidectomy, and preoperative TSH levels were significantly correlated with log-transformed TSH (lnTSH). The modified SOSS (category) based on recent stressors on OQ interview was significantly associated with lnTSH. In the GLMM with modified SOSS (category), the lnTSH increased by 2.3 and 0.56 in the unconscious high- and high-risk groups, respectively, compared to that in the low-risk group (P<0.05). The calculated power of this study was 0.92 based on alpha=0.05. CONCLUSIONS TSH had a significant relationship with stress and the extent of thyroidectomy. An OQ supported the SOSS to help detect unrecognized stressors. TSH has potential utility as a stress marker combined with the modified SOSS (category) with sufficient power. However, questionnaires on social environments and research on coping strategies for stress are necessary for future studies.


Assuntos
Glândula Tireoide , Tireotropina , Humanos , Glândula Tireoide/cirurgia , Estudos Prospectivos , Tiroxina , Tri-Iodotironina , Biomarcadores
18.
Front Endocrinol (Lausanne) ; 13: 1054983, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36407302

RESUMO

The thyroid operates within a complex system of homeostatic regulation, where the level of thyrotropin (TSH) influences the rate of secretion of the principal thyroid hormones, thyroxine (T4) and triiodothyronine (T3). The devastating consequences of untreated thyroid dysfunction have been evident for centuries. Indeed, sources from antiquity described goitre and cretinism, two of the clinical sequelae of untreated overt thyroid disease. It was not until the first part of the 19th century that goitre and cretinism were first associated with iodine status; however, the endocrine function of the thyroid was not clearly identified until the early part of the 20th century. Three principal innovations in the 20th century supported the use of levothyroxine (LT4) replacement therapy for the management of hypothyroidism: a practical technique for the synthesis of LT4 suitable to support pharmaceutical use (late 1940s), the discovery that LT4 is converted to the active thyroid hormone, T3, in the peripheral tissues (1970), and the development of robust and sensitive assay methodology for measuring thyroid hormones in the blood (1960 onwards). Synthetic LT4, titrated to bring the level of TSH within a predefined "normal" reference range, is now established as the mainstay of treatment for hypothyroidism, and provides adequate restoration of thyroid hormone function for most people with this condition. Future research will explore further the nuances of the hypothalamic-pituitary-thyroid axis, and the place, if any, for T3 within the management of thyroid dysfunction.


Assuntos
Hipotireoidismo Congênito , Bócio , Humanos , Tiroxina , Tireotropina , Hormônios Tireóideos , Bócio/tratamento farmacológico
19.
Medicina (Kaunas) ; 58(11)2022 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-36363515

RESUMO

Sulfonamides are among the most used drugs in beekeeping due to their effectiveness, despite their long-term persistence in tissues. Bee honey containing such residues poses numerous risks to human health. The aim of the study was to evaluate the effects on immunological and hematological parameters of Wistar rats produced by sulfonamide residues in bee honey, through the evaluation of various blood parameters such as triiodothyronine and thyroxine levels, hematocrit, hemoglobin, red blood cell count and mean corpuscular hemoglobin concentration in a given volume of erythrocytes following administration of sulfonamide-containing honey. The hematological and immunological parameters showed significant variations in the group of rats that had been fed with honey spiked with sulfonamides compared to the control group. Changes in hematological indices were demonstrated in terms of a significant reduction in the number of erythrocytes, the amount of hemoglobin, and the value of hematocrit, thus confirming the induction of anemia in the tested group. Investigation of thyroid function through the analysis of triiodothyronine (T3) and thyroxine (T4) and their ratio showed a very significant decrease in plasma thyroxine levels in laboratory rats that were fed sulfonamide-spiked honey compared to the control group. The mean T3 concentration decreased from 0.70 ± 0.14 ng/dL to 0.34 ± 0.03 ng/dL, while the mean T4 concentration was reduced from 4.50 ± 0.30 µg/dL to 3.32 ± 0.21 µg/dL, thus demonstrating toxic effects on thyroid function. In sum, the presence of sulfonamides induced significant changes in the evaluated parameters indicating that the consumption of contaminated honey samples represents a high risk factor for thyroid dysfunction with potentially serious health impacts.


Assuntos
Mel , Tri-Iodotironina , Humanos , Ratos , Animais , Tiroxina , Ratos Wistar , Sulfonamidas/efeitos adversos , Hemoglobinas/análise , Sulfanilamida
20.
Front Immunol ; 13: 1039166, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36389812

RESUMO

Anti-thyroid antibody (ATA) positivity affects 1 out of 9 women in childbearing age and presents a significant risk for infertility. Emerging evidence indicates that alterations in the B cell receptor induced calcium (Ca2+) signaling could be key in the development of autoimmunity. We aimed to investigate the Ca2+ flux response of B lymphocyte subsets to BCR stimulation in Hashimoto's thyroiditis and related infertility. We collected peripheral blood samples from ATA+, infertile, euthyroid patients (HIE), hypothyroid, ATA+ patients before (H1) and after levothyroxine treatment (H2), and age-matched healthy controls (HC). All B cell subsets of ATA+, infertile, euthyroid patients showed elevated basal Ca2+ level and hyper-responsivity to BCR ligation compared to the other groups, which could reflect altered systemic immune function. The Ca2+ flux of hypothyroid patients was similar to healthy controls. The levothyroxine-treated patients had decreased prevalence of CD25+ B cells and lower basal Ca2+ level compared to pre-treatment. Our results support the role of altered Ca2+ flux of B cells in the early phase of thyroid autoimmunity and infertility.


Assuntos
Doença de Hashimoto , Hipotireoidismo , Infertilidade Feminina , Humanos , Feminino , Tiroxina , Autoanticorpos
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